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<html>
	<head>
		<meta charset="utf-8">
		<title></title>
		<script type="text/javascript">
			var x = 10;
			var y = 100;
			console.log(x*y);
			console.log(x);
			{
				var x = 100;
				console.log(x);
			}
			console.log(x);
			/* 
			 es6的新标准 
			 */
			let z = 10;
			console.log(z);
			{
				/* 代码段中let定义的变量的作用域只在代码段中，代码段结束 代码段中定义的let变量生命周期也结束 */
				let z = 100;
				console.log(z);
			}
			console.log(z);
			
			/* 
			 es6新增了常量的定义方式const----
			 常量值不能改变，若改变则运行报错 
			 */
			const sysname = "sysname001";
			console.log(sysname);
			/* sysname = "sys";
			console.log(sysname); */
			
			 
		</script>
	</head>
	<body>
		<h3>es6新标准案例</h3>
		<script type="text/javascript">
			 
		</script>
	</body>
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